Magnetic resonance imaging (MRI) is a non-invasive imaging method that utilizes nuclear magnetic resonance techniques to render images within a patient's body. Typically, MRI systems employ the use of a magnetic coil having a magnetic field strength of between about 0.2 to 3 Teslas. During the procedure, the body tissue is briefly exposed to RF pulses of electromagnetic energy in a plane perpendicular to the magnetic field. The resultant electromagnetic energy from these pulses can be used to image the body tissue by measuring the relaxation properties of the excited atomic nuclei in the tissue.
During imaging, a static magnetic field produced by the MRI system can saturate ferrite materials used in circuits such as inductors and transformers within implantable medical devices such as pacemakers or cardiac defibrillators. Saturation of the ferrite components can disrupt the functionality of such devices. Accordingly, there is an ongoing need for devices and methods for shielding medical devices from magnetic fields during medical procedures such as magnetic resonance imaging (MRI).